JACK support

[schoappied]

Add JACK support so that you can connect and synchronize pro audio application to openshot!
Also make sure JACK Transport is possible for synchronization.

http://jackaudio.org/

[Dan Dennedy (dan-dennedy)]

Install pulseaudio-module-jack and you can do this today minus transport sync.
http://packages.ubuntu.com/lucid/pulseaudio-module-jack

[GMaq (info-bandshed)]

Hello,

The main reason for Openshot to use JACK would be the above mentioned syncronization with pro audio apps like Ardour and perhaps even more importantly access to dozens of JACK Client Plugins and various LADSPA and LV2 plugins. Access to these types of EQ, Compression and Dynamics would rival the already impressive filter set on the Video side of Openshot.

Although Pulseaudio may be fine for general desktop use it is a kludgy mess when used with JACK, many Ubuntu (and Ubuntu Studio) users who do pro audio uninstall Pulesaudio before they do anything else. AV Linux for instance does not even come with Pulseaudio due to it's issues with JACK.

I would respectfully suggest that Openshot would very much benefit from direct JACK support and it would open up a whole new world of audio processing and restoration capabilities.

[Andy Finch (fincha)]

PyJack has recently been updated to version 0.2 (it hadn't been updated for ages, I thought it was dead), so there is a possibility to use that for syncronization support - but I don't think it is included in any distributions repositories, so we'd probably have to bundle the file with Openshot itself. Apart from that, there aren't many possibilities to include JACK support (being a Python program).

@GMaq - in AVLinux, are you using libsdl1.2debian-alsa as you have no PulseAudio support?

That's another issue as well, how to effectively manage the PulseAudio situation if you want to use JACK? A lot of users will have PulseAudio on by default, to enable JACK we'd have to manage that somehow.

[GMaq (info-bandshed)]

Hello Andy,

Thanks for the reply. As I have have said to Jonathan...I have a lot of ideas but little coding experience so if what I ask is impossible or difficult forgive my ignorance.

To answer your question, yes AV Linux uses libsdl1.2debian-alsa. I recall reading awhile back about using pyjack with Blender to sync with Ardour, I can't recall which version of pyjack it was though and I haven't personally tested it. So far on the video side of things having no Pulseaudio hasn't been detrimental to AV Linux...even LiVES will work with sox or JACK and Cinelerra was around long before Pulseaudio as I'm sure you know.

I understand many Openshot users won't know or care about what JACK can do, but the extended functionality would take Openshot's capabilities far into the "Prosumer" market.

Thanks for even looking into this. -GLEN

[Andy Finch (fincha)]

Glen - it certainly looks possible to do, it's just how we manage those users on 'stock' distributions from not messing up their PulseAudio - I don't think we want a raft of 'my sound's stopped working' reports!

But I understand that those that use AVLinux, UbuntuStudio or some other multimedia distribution would benefit from this (myself included).

If there's a way to detect if PulseAudio is running, then we can just prevent the switching on of JACK support in Openshot by the user. Hopefully a suitable warning would discourage the average user from trying to messa round with their sound settings.

[GMaq (info-bandshed)]

Andy,

That sounds promising, I haven't switched over to packages for Openshot itself in AV Linux yet, although all of it's support libs are official Debian packages. Jonathan has made me aware that it's in Debian Sid. The point is if I can help with testing this I run from an unzipped tarball placed in /opt which may be a little easier to play with patches and supplemental scripts etc than using a Deb. Please let me know if I can help. Thanks very much for ALL of your efforts. I'm glad you can see the benefit of JACK support without having to just take my word for it :)

For some reason I'm not getting email notifications on this bug so I'll keep checking back to see what's up, If there are significant AV Linux donations (I'm working on a special release right now with "Beat" magazine) I'd like to send a donation upstream to Openshot again, this is a phenomenal app and the overall vibe here with Jonathan and the team is so positive!

Here is the article I mentioned before about pyjack in case it helps http://www.jpbouza.com.ar/ESP2/tutoriales/gnulinux/blenderardour/id/en

Thanks again Andy

[Andy Finch (fincha)]

Glen - You're not down as being a subscriber to this bug, which is probably why you are not getting mails. Try the Subscribe link over there on the right, that should hopefully do it.

[GMaq (info-bandshed)]

Well colour me stupid! I assumed I was subscribed since the bug was affecting me...I'm locked and loaded now. Nice to see the status changes on this bug!

[jv13613 (jv13613)]

I don't know if this will help but

in wikipedia for MLT http://en.wikipedia.org/wiki/Media_Lovin%27_Toolkit it says it is modular with jack.

"Modules

    Integration with many libraries for multimedia including FFmpeg, Jack, LADSPA, SoX, SRC (libsamplerate), frei0r, GTK+, Qt, and SDL"

This might help on the coding side of things.

[Andy Finch (fincha)]

There is currently no Jack transport support in MLT, which is the main thrust of the request.

[jv13613 (jv13613)]

EDIT: its at http://www.mltframework.org/twiki/bin/view/MLT/Features

[jv13613 (jv13613)]

I don't get why MLT would put that as a feature???

[Andy Finch (fincha)]

I think MLT supports Jack effects, but I'm not too sure.

[Andy Finch (fincha)]

After researching this, the only way we could build in support for Jack transport at this time is via an external library that is currently not included in the repositories (for Fedora & Ubuntu anyway). This makes it impractical to do at the moment. We'll have to revisit it if/when it does get included or MLT add in Jack Transport support.

[GMaq (info-bandshed)]

Bummer!... but understandable for the time being. Thanks for looking into it, I'm sure almost nonexistent demands for JACK support in the recent survey takes it down several notches on the todo list as well. I do reiterate that many users are likely unaware of what JACK plugin support and transport could accomplish especially for restoration work but that's an issue for another time.

Looking forward to 1.2.0, great work so far!!